1. Field Of The Invention
The invention herein pertains to slidable structural members and particularly to furniture structural members such as arm or back supports as may be manually adjusted and operated with a release button.
2. Background And Objects Of The Invention
The present invention relates in general to mechanisms which provide for the selective adjustment and positioning of moveable structural components relative to one another. As will be seen, the device is ideally suited for use in furniture, particularly office furniture, where the current market emphasis on ergonomic design calls for adjustable furniture structures such as used with certain chairs that can be adjustably positioned to fit different individuals with various heights, weights and job tasks.
Primarily the device is intended for the positioning of components where frictional locking is not sufficient and load forces are substantial, such as is the case with the vertical adjustment of chair arms and backrests. Here the device can be advantageously used to vertically position chair arms or backs to accommodate users of different body heights and proportions.
In the prior art, chair arm vertical adjustment has been accomplished by the use of devices including telescoping members provided with knob operated frictional locking means which are strength dependent and require considerable effort on the part of the user to achieve positioning. An equal amount of effort is thus required to readjust such devices, which is inconvenient and time consuming. In addition effort required to adjust to the friction/strength dependent devices, the knobs are unsightly and interfere with other objects or the user. These friction/strength dependent devices are incapable of passing tests specified by government and industry standards and are generally considered unsafe. Also, in situations where the same chair is used by several work shifts it is often the case that occupants find it difficult to sit comfortably since adjustment of the chair between shifts is difficult and sometimes not possible. Other methods for vertical adjustment include telescoping members provided with knob operated two-toothed gears. These remain unsightly, produce loud sounds when operated and have tendency to collapse responsive to impact under certain circumstances.
It is thus an object of the present invention to provide a device for the quick yet firm, accurate manual positioning and changing of one structural component relative to another.
It is another object of the invention to provide a mechanism to allow the positioning of chair arms or backs relative to the chair set at any of a predetermined number of positions within a specific range, while doing so with an esthetically pleasing device.